Purpose: This study aims to investigate the effectiveness of a teaching method (TLS (Teaching/Learning Sequence)) based on a social constructivist paradigm on students' conceptualisation of classification of food. Design/methodology/approach: The study compared the TLS model developed by the researcher based on the social constructivist paradigm with the Regular Teaching Method (RTM) in use in the school. Students exposed to the TLS model constituted the experimental group, while the students exposed to the RTM constituted the control group. The design was a pre-test/post-test control design with a retention-phase. Findings: Results before intervention revealed gross misconceptions of pupils' classification of food, while after intervention there was significant improvement of the TLS over RTM. Research limitations/implications: The context of the research is limited to students' conceptualisation of classification of food items into the five classes of food, i.e. carbohydrate, protein, fat, vitamin, and mineral. Although food group allocation was validated from previous literature, it is still a potential limitation as a single food item may contain more than one nutrient, which makes its classification in a single food class difficult. Practical implications: Understanding whether students' conceptualisation of classes of food is changed by the information they received by established methods would be valuable when devising methods of delivering nutrition education. Social implications: Food provision in schools must support the messages that pupils receive through the formal curriculum. Originality/value: Education can be immensely helpful in the pursuit of better understanding by children regarding healthy eating. (Contains 5 tables and 1 figure.)